[PATCH 18/19] KVM: PPC: Book3S HV: add passthrough support

[Cédric Le Goater]

On 1/29/19 5:12 AM, Paul Mackerras wrote:
> On Mon, Jan 28, 2019 at 07:26:00PM +0100, Cédric Le Goater wrote:
>>
>> Is clearing the PTEs and repopulating the VMA unsafe ? 
> 
> Actually, now that I come to think of it, there could be any number of
> VMAs (well, up to almost 64k of them), since once you have a file
> descriptor you can call mmap on it multiple times.
> 
> The more I think about it, the more I think that getting userspace to
> manage the mappings with mmap() and munmap() is the right idea if it
> can be made to work.

We might be able to mmap() and munmap() regions of ESB pages in the RTAS 
call "ibm,change-msi".  I think that's the right spot for it. 

Thanks,

C.